Makefile.spl: Move generated AT91SAM NAND image boot.bin to spl directory

This patch moves the AT91SAM NAND booting SPL image "boot.bin" which
includes the ECC values from the root directory into the spl directory,
where all SPL related images are located.
Signed-off-by: NStefan Roese <sr@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Andreas Bießmann <andreas@biessmann.org>
Cc: Eugen Hristev <eugen.hristev@microchip.com>
Reviewed-by: NHeiko Schocher <hs@denx.de>
Tested on the taurus board:
Tested-by: NHeiko Schocher <hs@denx.de>

scripts/Makefile.spl

@@ -179,10 +179,10 @@ MKIMAGEFLAGS_boot.bin = -T atmelimage
 ifeq ($(CONFIG_SPL_GENERATE_ATMEL_PMECC_HEADER),y)
 MKIMAGEFLAGS_boot.bin += -n $(shell $(obj)/../tools/atmel_pmecc_params)
 
-boot.bin: $(obj)/../tools/atmel_pmecc_params
+$(obj)/boot.bin: $(obj)/../tools/atmel_pmecc_params
 endif
 
-boot.bin: $(obj)/u-boot-spl.bin FORCE
+$(obj)/boot.bin: $(obj)/u-boot-spl.bin FORCE
 	$(call if_changed,mkimage)
 else
 ifdef CONFIG_ARCH_ZYNQ
@@ -225,7 +225,7 @@ endif
 endif
 
 ifeq ($(CONFIG_SYS_SOC),"at91")
-ALL-y	+= boot.bin
+ALL-y	+= $(obj)/boot.bin
 endif
 
 ALL-$(CONFIG_SPL_X86_16BIT_INIT) += $(obj)/u-boot-x86-16bit-spl.bin